As defined in Article 4 of the Korean Food Sanitary Law which provides basis for prohibition against marketing of hazardous foods and the like, the term “hazardous substance or hazard” refers to a biological, chemical or physical contaminants or condition which may have potency to cause an adverse effect in human health. Other foreign substances or deterioration having no direct impact on the consumer's health is not considered hazardous. Hazards or hazardous substance can be classified as shown in Table 1 below.
TABLE 1HazardsDetailsBiologicalBacillus cereus, Clostridium perfringens, Clostridium botulinum,hazardsCampylobactor jejuni, Escherichia coli O157:H7, Listeria monocytogenes,Salmonella spp., Yersinia enterocolitica, Staphylococcus aureus, Vibrioparahaemolyticus, viruses, parasites, etc.ChemicalNatural toxins (fungal toxin, shell toxin and mushroom toxin), animal drughazardsresidue, hormones, pesticide residue, endocrine disruptors (environmentalhormones), heavy metals (mercury, lead and cadmium), allergens, unapprovedfood additives, chemicals (acrylamide, etc.) that occur during processing andstorage, radioactivity, etc.PhysicalForeign substances, glass, metals, stones, twigs, wood leaves, wood, rust,hazardsnoxious insects, jewels, accessories, hair, etc.
The present invention particularly relates to the detection of biological hazards, which include microorganisms such as fungi, bacteria, viruses and parasites. Biological hazards can be introduced into a warehouse during the production and distribution of food, and can also contaminate food as included in a food produce itself a warehouse environment, and a production and processing equipment, or by unsafe handling.
Food poisoning outbreaks caused by hazards in foods derived from agricultural, marine and livestock products have a serious impact on public health. The domestic economic loss caused by the food poisoning outbreaks reaches to about 1.3 trillion Won (Korean currency) per year due to the absence of a suitable method and system for early detection of the hazards. Among them, microbiological food poisoning may be most frequently caused by bacteria and virus, and viral food poisoning accounts for about 34-40% of microbial food poisoning and causes an economic loss of about 4 billion Won (Korean currency).
Although the sanitary condition of the modern urban environment has been improved, food poisoning caused by norovirus infection has been increased recently, and the number of death associated with norovirus infection in Japan and Europe was recorded as 6 and 12, respectively, in the year of 2012. Moreover, the US Centers for Disease Control and Prevention reported that norovirus infection caused a total of 348 outbreaks during a period from 1996 to 2000.
In addition, it has been also reported that the rate of positive antibody test against hepatitis A virus (HAV) in young and adults has decreased, and accordingly, the cases of HAV infection virus have increased. Hepatitis A virus disease is a highly infectious and waterborne disease and may cause an acute inflammatory liver condition. This virus infects humans through faces or via an oral route, and it is estimated that about 1.5 million cases of HAV infection occur worldwide annually. In South Korea, hepatitis A disease has been designated as an infectious disease since 2000, and the number of HAV infection cases has increased from about 100 cases in 2001 to about 7,655 cases in 2010.
According to this tendency, norovirus and hepatitis A virus infection have been designated as group 1 infectious diseases since 2010 and the cases of those viral infections have been reported via a mandatory surveillance system to the Korea Centers for Disease Control and Prevention.
Meanwhile, detection of hazardous virus in agricultural product samples such as fruits and vegetables have been reported in Korea and other countries. When contaminated food and underground water infected with a virus is consumed without being cooked or boiled, viral infection may occur. For example, infection with norovirus and hepatitis A virus may be particularly associated consuming a raw oyster. In Table 2, the major sources of norovirus and hepatitis A virus and prevention methods thereof are listed.
TABLE 2Characteristics and initialSources that causesymptoms (latent stage)infectionPreventionNorovirusproliferates only in humanwater or foodrestraint of shells suchintestinal tractscontaminated withas oysters, produced inviable in naturalhuman fecescontaminated sea areasenvironments for a longsecondary infectionshells should beperiod of timeby a person infectedconsumed after heatingthere is no antiviral agent orwith norovirus.(at 85° C. or higher for 1vaccineminute or moreoccurs mainly in winterthorough managementnausea, vomiting, diarrhea,of personal sanitationabdominal pain, anduse of tap water forheadache (24-48 hours)pretreatment ofvegetablesthorough managementof contaminationsources (toilet, etc.)around facilities that useunderground water.Hepatitis AFever, nausea, vomiting, contaminatedcooking atvirusabdominal pain, fatigue, anddrinking waterrecommendedjaundice (10-50 days)food that came intotemperaturecontact with a personall shells should beinfected with hepatitiseaten boiledA virusthorough managementwater, strawberries,of personal sanitationmollusk, fishes andshells.
Thus, a method for rapid detection of virus to assess viral contamination in food from agricultural, marine and livestock products and assure safe food supply to consumers may prevent the above-described socioeconomic loss.
Typically, food poisoning virus can be diagnosed by an enzyme immunoassay or molecular biological assay using a monoclonal or polyclonal antibody. In addition, a diagnostic method based on chip technology has been developed recently.
For detection of virus in food, at first, virus recovered from food samples can be obtained by eluting and concentrating the virus in the eluate is performed before the detecting the virus. Elution of virus may be performed using various elution buffers depending on analysis agencies. The eluted virus is subsequently concentrated using an immunomagnetic capture, an organic flocculation or a PEG (polyethylene glycol) precipitation method. The immunomagnetic capture method may reduce the time for concentrating virus, but may be an expensive method due to use of an expensive antibody. Organic flocculation and the PEG precipitation methods may have disadvantages as a process for concentrating the virus due to time-consuming and complicated procedures, which further cause increase in loss of virus, thus reducing the sensitivity of detection.
Bacterial waterborne diseases such as typhoid fever, cholera, and bacterial and amoebic dysentery have greatly decreased since safe drinking water, sanitation systems and methods have been provided. However, protozoa cannot be easily removed in a water purification process due to high resistance to chlorine disinfection. For this reason, the incidence of diseases caused by Giardia and Cryptosporidium may be still problematic. In addition, a single unit of waterborne virus may cause infection, and thus contamination with the virus may occur without detection of an indicator microorganism. Infection with virus occurs when contaminated water is consumed without treatment or with insufficient treatment from a private or simplified water purification system. For example, in underground water, various hazardous substances are detected mostly due to the contamination with environmental pollutants. Particularly, norovirus that is contagious through excretes of infected patients is in substantially small size such that it easily penetrates soil. Further, norovirus can be viable for a long period of time even in underground water that is maintained at low temperature. Accordingly, there is still a need for providing drinking water free from biological hazards such as virus by methods of detecting viruses in a short time.